Michael j



Aug. 2 8, 1923.

M. J. owENs SHEET GLASS DRAWING MECHANISM Filed April 27. 1922Arr'aRA/EY Patented Aug. 28, 1923.

UNITED STATES PATENT OFFICE.

MICHAEL J. OWENS, OF TOLEDO, OHTO, ASSIGNOB TO THE LIBBEY-O/VENS SHEETGLASS COMPANY, OF TOLEDO, OHIO, VA CORPORATION OF OHIO.`

SHEET-GLASS-DRAWING VIECHANISM.

Application filed April 27, 1922. Serial No. 556,848.

To all whom it may concern `Beit known that I, MICHAEL J'. Owens, acitizen of the United States, residing at Toledo, in the county of Lucasand State of Ohio, have invented new and usefullmprovements inSheet-Glass-Drawing Mechanism, of which the following is a specification.

This invention relates to a sheet glass drawing apparatus and moreparticularly to an improved form of support for the pot or containerholding the molten glass from which the sheet is drawn.

In a sheet drawing apparatus oit the Colburn type` as set forth torexample in the patent to I. WV. Colburn, l,2el8,899, granted Dec. Ll,1917, the molten glass il'rom which the sheet is drawn is carried in ashallow receptacle or draw-pot, beneath which is a heating chamber jt'ormaintaining the glass at the proper drawing temperature. 'lhere must besupports within the heating chamber for this draw-pot, and thesesupports are in the form of arches, to allow for the tree passagetherethrough or' the hot gases. As shown :for example in Patent1,2l-8,809, referred to above, the upper member or tier orF each ofthese supports has the supporting arches turned upwardly so that the potis carried by a series of spaced legs or posts, between which pass thehot gases. This has resulted in unequal heating o't' the glass withinthe pot, there being cooler areas above the contact points ot thesupporting posts and hotter areas therebetween caused by the closerContact ol the heating gases. Since the sheet is drawn from the pot on aline parallel to the series of supporting posts, there will resultalternate hotter and cooler areas across the width ot the sheet.

The object ot 'the present invention is to avoid this unequal heatingoit the molten glass inthe pot, and the consequent inequalities in theglass sheet. This result has been accomplished by turning over the uppersupporting member so that the arches point downwardly and the openpassages are removed from direct contact with the pot. The upperuninterrupted side of the supporting member is in continuons contactwith the pot, and the edges of this member' are beveled 'ott' to make anarrower Contact ing edge. Any cooling effect that this edge has uponthe molten glass will be equally distributed across the pot, and hencewill not result in inequalities in the sheet.

rlhe invention will be better understoodifromthe following detaileddescription of one approved toria of the apparatus.`

The accompanying drawing is a perspective View oit the draw-pot. and itssupports, the nearer side being broken away in longitudinal verticalsection.

At l is shown the delivery end ot the cool. ing or refining chamber of acontinuous tank furnace. '.l`he upwardly sloping bottom wall 2 of thistank joins flush with the bottom ol the shallow draw-pot 3, which holdsthe glass from which the sheet 7 is drawn. lhe draw-pot 3 is closed atthe far end by wall a, similar to the side-walls 5, and the inner end isopen at (i to communicate with the tank l. The outline of the sheet 7 isindicated in dotted lines; the level of the molten glass in the draw-potand tank also being .indicated by dotted lines as at 8.

Beneath the draw-pot and extending be yond the two sidesl and the closedend thereol, is a heating chamber indicated generally at 9. The ends andsides of this chamber are closed, and the open front end of the pot issupported on the lront wall 10 of this chamber 9. 'lhe rear wall 11 ofchamber 9 is spaced somewhat beyond the farther end of the pot. leavinga vertical passage 12 'l'or the heated gases to pass up around the end,otx .the pot and pass out through iiue 13. rThe side extensions ofchamber 9 beyond the sides of the pot are closed at the top by slabs 14thus Ylorniing heating cham bers extending part way up around the sidesof the pot to prevent the undue cooling` of the molten glass near theseedges.

The draw-pot is supported within the chamber 9 beneath its rear edge andat an intermediate point by transverse arched supports or stools 15 and1G. These are silica blocks or similar refractory material, and may beformed as a single block extending the width oit the pot, or may bebuilt up ot a series ot separate blocks such as 17, 18, 19, etc. Inprior constructions the upper stool 16 has been positioned with thecontinnous fiat side down and resting upon the upper continuous tace otthe lower stool 15. This le'lt the open arches 20 adjacent the lloor ofthe chamber, and an upper series of arches adjacent the bottom of thepot between the series of spaced legs or posts 21 upon which the potrested; This construetion vis" shown in the Colburn patent, 1,248,809,referred to above, and in several "similar patents, ,lt has kbeen foundthat cooler arasin thefx'nolteri glass were 'formed above the posts 21,with alternate hotter areas therebetween corresponding` to the openarches through which pass the hot gases.

According to the. present invention, the

upper stools 16 have been inverted, as shown in the drawinggf,l so-thatthe legs 2l rest upon the lower stools-15, and the pot is carried bythe-continuoi'isY flat upper surface 22 olir the stool; `Also the sideedges of the stoolv are 'eveled off so as to lettre the upper edge 22erthestol as narrow as is practicable to supportuth'e draw-pot; lVhilethis supporting edge 22 doubtless' has a cooling effect upon' the glassthereabove, this influence is `parallel to the sheet source anddistributed equally across the width ot the pot, and atfects thetemperature ot the sheet 7 uniformly-at all transverse points.-

Thi's construct-ion eliminates vthe alternate hotand cold areas acrossthe width of the pot, which caused similar temperature variationsanfd-lconsequent irregularities in the sheet. The sheet is drawn fromglass of a uniform temperature and plasticity at all points Vacross thepot, has a uniform thick ness, and the'iiiormation of waves andwrinlrlles is larg'gely eliminated,

Claims: v

l.- In a sheet drawing mechanism, a

draw-potsupporting stool having an upper continuous uninterruptedpot-supporting surface, and havinggas passages Ytermed through its lower`pt'irtion. i

Qyln a' sheet glass drawing' machine, a

draw-plot supporting' stool having its under sui-tace eut away intervalsto form a series or open arches, and its upper pot-supyside cut-away tolor'rn a se porting surface continuous and uninterrupted.

3. ln sheet glass drawing machine, a drawepot supporting stool having'its under surtace-cut away at intervals to 'torni a series of open4arches, the `upper portion being beveled at the to torni a narrowcontinuous uninterrupted pot-supporting surace.

et; ln a sheet- Lglass drawing machine, in combination with a drawpotcontaining'the molten glass 'troni which the sheetis drawn, v

a heating;` chamliier beneath the draw-pot, and transv i' the chamber,eaclrsupport havinga con tinuous uninterrupted supporting` contact withthe plot, there being passages itor the hotgasses through the supportspaced below the upper pot-supif3ortiiig sur ace.

5. fina sheet glas.; tlrawir machine, in combination with a draw-petcontaining;l the molten glass trom which the sheet is drawn, atransverse sul'iportiiogiv member beneath the `pot positioned pai'failelto the vline oft draw of the sheet, the iiien'iber havingr its underside cutaway to tor-ni a series oit open arches, and its upperpot-supportingside in MICHAEL J. OW'ENS. i

se. supports for the irtiotcivithin

